Flare stack



FIG. 1 is a perspective view of a flare stack showing a new design.

FIG. 2 is a first side, elevational view thereof.

FIG. 3 is a second side, elevational view thereof.

FIG. 4 is a front, elevational view thereof.

FIG. 5 is a rear, elevational view thereof.

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines shown in FIG. 6 are included for the purpose of illustrating portions of the article that form no part of the claimed design. 

CLAIM The ornamental design for a flare stack, as shown and described. 